Most contracts don’t need to be in writing to be enforceable. Here are a partial list of some that are required to be in writing, in Oregon and Washington:
Contracts transferring an interest in land, or leasing it for more than one year – and if a broker or agent is used, his or her authority also has to be in writing.
Contracts that cannot, under any circumstances, be performed within one year.
Contracts to sell goods worth more than $500 (if the other side denies the agreement)